As a power source of a motor for generating a driving force of Electric Vehicles (EV) or Hybrid Electric Vehicles (HEV), a secondary battery such as a lithium ion battery or a nickel hydrogen battery has been actively pursued and developed.
Japanese Patent Laid-Open Publication No. (HEI) 11-102711 discloses a secondary battery having an electrode structure wherein the same electrodes are formed at both surfaces of a resin film (see FIG. 1).